UX Affordance for Distinguishing User-Created from System-Generated Content

Our system has a collection of objects (school classes, to be specific) that are currently all system-generated through an integration with an external database. The classes are displayed as a grid of tiles on a page.

We're adding the functionality to allow teachers to create their own school classes that will mostly be functionally identical to the ones created by the system, but with a couple of exceptions, and we'd like to distinguish easily between user-created and system-generated classes visually.

Is there an affordance or design pattern that would read well as "user-created" for this purpose?